Gelatin is often used as a binder for silver halide photographic light-sensitive materials.
Since gelatin is highly capable of swelling and gelling and easily crosslinkable with various hardeners, it serves excellently as a binder to uniformly coat a material which is sensitive to high temperature, such as light-sensitive silver halide, over a wide area of base by adjusting the physical properties of coating solution.
In silver halide photographic light-sensitive materials, silver halide grains change to very hard metallic silver during development while the gelatin layer is in a swollen condition with sufficient water absorption. This interferes with the recovery of the emulsion layer even after drying, which leads to dimensional difference before and after processing even within the same light-sensitive material.
Meanwhile, it is a well-known practice to improve physical properties of a light-sensitive material by adding polymer latex to the silver halide emulsion layer or backing layer. Examples of such methods are described in Research Disclosure No. 19951, Japanese Patent Examined Publication Nos. 4272/1964, 17702/1964 and 13482/1968, U.S. Pat. Nos. 2,376,005, 2,763,625, 2,772,166, 2,852,386, 2,853,457 and 3,397,988 and other publications. Also, Japanese Patent. Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O. P. I. Publication) Nos. 38741/1984, 296348/1986, 284756/1986 and 285446/1986 and other publications disclose methods in which fine oil drops of paraffin or vinyl polymer are added. However, none of these methods are satisfactory, and further improvements have been needed. The problem to be solved is that conventional latices form a film (aggregation) and fail to have an effect even when the amount of addition is increased when they are added to gelatin in large amounts. This situation is undesirable for a dimensional stability improving effect; it is desired that a means will be developed of improving the wide variation of dimensional difference before and after processing depending on ambient temperature.